1. Field of the Invention
The present invention relates in general to compressors for use in a refrigerating cycle of an automotive air conditioning system, and more particularly to compressors of a swash plate type.
2. Description of the Prior Art
In order to clarify the task of the present invention, one conventional compressor of the above-mentioned type will be outlined, which is described in Japanese Patent First Provisional Publication 7-103138.
The compressor comprises a case having a crank chamber is therein, a drive shaft rotatably installed in the case, a drive plate fixed to the drive shaft to rotate therewith, a sleeve axially slidably disposed on the drive shaft, a journal pivotally mounted on the sleeve, a swash plate tightly disposed on the journal, a transmission/hinge mechanism arranged between the drive plate and the journal for transmitting the rotation of the drive shaft to the journal while permitting a pivotal movement of the journal relative to the sleeve, a plurality of cylinders defined in the case, and a plurality of pistons driven by the swash plate to be reciprocatively moved in the cylinders. To a back side of the case, there is mounted through a valve plate a rear housing which has refrigerant intake and exhaust chambers formed therein.
The transmission/hinge mechanism comprises a first arm projected from the drive plate, a second arm projected from the journal, an elongate opening formed in the first arm and a pin held by the second arm and slidably engaged with the elongate opening. When, due to rotation of the drive shaft, the drive plate is rotated therewith, the rotation of the drive plate is transmitted to the journal through the pivotally engaged first and second arms while permitting the pivotal movement of the journal on the sleeve. During this, due to an inherent construction of the transmission/hinge mechanism, leading portions (which are termed in view of the direction in which the drive plate rotates under normal operation of the compressor) of the pivotally engaged first and second arms are applied with a marked stress as compared with trailing portions of the same. That is, under operation of the compressor, the maximum compression load of the pistons is applied to the leading portions through the swash plate. This phenomenon tends to cause a poor rotation transmission from the drive plate to the journal as well as a poor pivoting movement of the journal relative to the sleeve.
Hitherto, many attempts have been made for eliminating the above-mentioned drawbacks. However, almost all the attempts have failed to exhibit satisfied results.